Memory devices tend to be used in a variety of contexts as technology advances. For instance, some usages may require that a memory device retain data for a long period of time, e.g., a hard disk storage device. Another usage may not necessarily be concerned with memory retention, but may require limited power consumption. For example, mobile devices often require low power memory due to limited battery capacity. Other contexts may require high reliability, low bit-error rate, high throughput, or the like, from a memory device. For various reasons, commercial and non-commercial users may have different expectations of endurance, reliability and the like, while produces of the memory device would prefer to limit the amount of devices produced specialized purposes. One type of memory device commonly used is a non-volatile memory known as flash memory. A flash memory is a type of EEPROM (electrically-erasable programmable read-only memory) that can be erased and reprogrammed in blocks.
Many modern personal computers (PCs) have their BIOS stored on a flash memory chip so that it can easily be updated if necessary. Such a BIOS is sometimes called a flash BIOS. In other instances, hard disks contain buffer memory which may be stored on a flash memory chip. Flash memory is also popular in portable electronic devices because it enables the manufacturer to support new communication protocols as they become standardized and to provide the ability to remotely upgrade the device for enhanced features. NOR and NAND flash memory devices are two common types of flash memory devices, so called for the logical form of the basic memory cell configuration in which each is arrange. Memory devices usually include trim circuits that are programmed to output parameter values used to provide a variety of options for algorithms that control the operations of the memory device. Such parameters may include timing, pulse counts, applied voltage levels, etc. The trim parameters are usually programmed once for a memory device and are rarely changed once the memory device has reached production.
However, when memory devices reach production, producers would like to use a single set of trim parameters for the memory device. Accordingly, if a customer requires, for example, high throughput, from the memory chip, and the memory chip is configured with trim parameters aimed at long endurance, the customer would have to request a new production of memory devices with long endurance trim parameters. This results in wasted time, money and effort on both the production and the customer side. Similarly, when a customer uses a memory device, it is difficult to know the correct trim parameters to use for long endurance to minimize error rate.
Therefore, there is a need in the art for a method and apparatus for a memory device with variable trim parameters and for autotuning the trim parameters.